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Offline scooter  
#1 Posted : 21 February 2011 00:43:10(UTC)
scooter

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I'm using the last version over WXP and i have one problem using degrees:
The acos and asin functions seems didn't work because i get the result "Index out of the matrix limits" it works well in radian and in certain angles like 0º, 60º and 90º but i can't get the acos(0.8) for example.
The error message is aproximated because i'm working in spanish and i get "Índice fuera de los límites de la matriz"
As in spain we use a comma as a decimal dot i changed it in the preferences but i get the same error with 0,8 or 0.8

Edited by user 21 February 2011 00:45:42(UTC)  | Reason: Not specified

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Offline omorr  
#2 Posted : 21 February 2011 10:26:40(UTC)
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Hello,

Very strange. I do not have any idea what has gone wrong.
acos(0.8)=0.64
acos(0,8)=0,64
Please double check what did you have in Tools|Optons|Interface Decimal symbol and Argument separator. Try to change it.

Regards,
Radovan
When Sisyphus climbed to the top of a hill, they said: "Wrong boulder!"
Offline scooter  
#3 Posted : 21 February 2011 13:32:25(UTC)
scooter

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You are working in radians, in radians works well but not in degrees:
acos(0.8)must be 36.86º and i get the error
however acos(0.5) = 60º works ok. With acos(0) and acos(1) works well too but not for all angles.
In radians all is working well.
Other strange thing: if i do sin(acos(0.8)) i get 0.6 that is ok but i can't get the angle value in degrees.
I tryed with the comma and dot for decimal sign and i get the same wrong resuts for both using degrees, using radians all is ok.

Edited by user 21 February 2011 13:35:38(UTC)  | Reason: Not specified

Offline omorr  
#4 Posted : 21 February 2011 15:51:40(UTC)
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Hello,
scooter wrote:
You are working in radians, in radians works well but not in degrees:
acos(0.8)must be 36.86º and i get the error
however acos(0.5) = 60º works ok. With acos(0) and acos(1) works well too but not for all angles.
In radians all is working well.
Other strange thing: if i do sin(acos(0.8)) i get 0.6 that is ok but i can't get the angle value in degrees.
I tryed with the comma and dot for decimal sign and i get the same wrong resuts for both using degrees, using radians all is ok.

Open in SMath Cloud
Just click into the result:
- then click into the rightmost placeholder that appears
- pres CTRL+SPACE to activate Dynamic assistance
- You will see the list
- Chose Angles (the first in the list)
- Press TAB

This way you changed the results from radians (number with unit "rad" or without the unit - to angles)
Number without the units are regarded as radians - if you want angles, you have to use the unit Angle-Degree.

I hope this helped. If you can not reproduce this, I do not know what is the problem - sorry.

Regards,
Radovan

Edited by user 21 February 2011 15:54:06(UTC)  | Reason: Not specified

When Sisyphus climbed to the top of a hill, they said: "Wrong boulder!"
Offline TheWizEd  
#5 Posted : 21 February 2011 15:59:12(UTC)
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scooter,

I have the same problem, 0.89 on Win7. If I change the Tools->Options->Angle Units to Degrees the the arc trig functions don't work. I get the same error message.

It appears Degrees can only be used as input to trig functions, not results. My guess.

Radovan has posted a good work around.

Edited by user 21 February 2011 16:03:17(UTC)  | Reason: Not specified

Ed
Offline omorr  
#6 Posted : 21 February 2011 16:26:11(UTC)
omorr


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Ah yes, I forgot that sorry Confusion

Thank you Ed for pointing out to this.

In the stable version 0.89 there is option Tools|Options|Angle units, and you can set it to Radians or Degrees. That can cause some problems, and should be avoided. Actually, just keep the default Radians as angle units and use "deg" or "º" unit for Degrees.

In the recent Beta 0.89.8 this option does not exist anymore. Numbers without units are regarded as Radians (or we can add the "rad" as unit) and if you want Degrees you must add the "deg" or "º" unit.

Regards,
Radovan
When Sisyphus climbed to the top of a hill, they said: "Wrong boulder!"
Offline scooter  
#7 Posted : 21 February 2011 21:46:18(UTC)
scooter

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Location: Spain

Thanks a lot i just starting to use SM and i'm not using units because i have a trouble with the complex units for the electric power in AC; W, VA, VAR seems that only W are reconized but i need all.

Well, degrees solved for now.
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